Space rock explodes over Siberia, injuring more than 1,000

The meteor that exploded across the sky Friday morning above Chelyabinsk, Russia, with the force of 20 nuclear bombs -- shattering windows and injuring more than 1,000 people -- may not actually be cause for much alarm, Boulder scientists say.

"This actually happens hundreds of times a day," said Doug Duncan, the director of University of Colorado's Fiske Planetarium. "Even ones that are basketball-sized -- those hit all the time. The reason it's not in the news is that most come down in the ocean or in mountains or deserts."

Duncan said that the Chelyabinsk meteorite, with an estimated diameter between 6 meters and 8 meters, was closer in size to a Volkswagen Beetle than a basketball, but that's still relatively small compared to anything truly threatening.

The meteorite, which hit Russia around 9:20 a.m. local time Friday (8:20 p.m. MST Thursday), was moving fast enough to go from Boulder to Denver in about a second, and it is estimated to have weighed about 10 tons. NASA said it exploded about 12 to 15 miles high, released 300 to 500 kilotons of energy and left a trail 300 miles long.

"There was panic. People had no idea what was happening," said Sergey Hametov of Chelyabinsk, about 930 miles east of Moscow in the Ural Mountains.

The shock wave blew in an estimated 1 million square feet of glass, according to city officials, who said 3,000 buildings in Chelyabinsk were damaged.

The Russian Interior Ministry said about 1,100 people sought medical care after the shock wave and 48 were hospitalized. Most of the injuries were caused by flying glass, officials said.

By pure coincidence, the Russian meteorite exploded the same day that 2012 DA14, an asteroid the size of an Olympic swimming pool, whizzed by earth from a distance of about 17,000 miles. Scientists knew about 2012 DA14, but the Russian meteorite caught the world off guard.

Municipal workers repair a damaged electric circuit outside a zinc factory in Chelyabinsk, Russia, that suffered a roof collapse Friday after a meteor exploded in the sky with the force of 20 nuclear bombs, injuring more than 1,000 people.
(
Oleg Kargapolov
)

"The small guys are almost impossible to detect with our current systems," said Bill Bottke, director of space studies at Boulder's Southwest Research Institute. "With these (asteroids) so far from earth, they don't reflect enough light to be very bright. We would have to have been exceedingly lucky to have seen this."

The U.S. government will allot about $20 million dollars this year to asteroid detection, though that's not going to prevent encounters like the one in Chelyabinsk.

"Twenty million dollars isn't peanuts, but it's not enough to find these small (asteroids)," Bottke said. "The smaller you go, the more expensive it gets."

A circular hole can be seen in the ice of Chebarkul Lake where a meteor struck near Chelyabinsk, Russia, on Friday.

The relatively mild threat of the "small guys" may help explain the lack of funding. Though they are numerous, they almost never affect human beings. Duncan estimates that the odds of being struck by a falling meteorite are about 100 times greater than the odds of being struck by lightning. In fact, only one American in the last 50 years has reported being hit by a meteorite -- and she walked away with just a few bruises.

"These things happen from time to time, but I don't go to sleep worrying about an asteroid hitting," Bottke said.

Despite the Russian meteorite's grand-scheme insignificance, scientists view it as a major learning opportunity.

"These meteorites give us a direct sample of what things were like when the earth and the moon and the solar system were all forming," Duncan said. "There's no place on earth that you could find a rock like this."

While you certainly aren't likely to stumble upon an asteroid fragment anytime soon, CU's Fiske Planetarium does house a 150-pound meteorite. Fiske is undergoing remodeling at the moment, but it will reopen this fall.

Should a Chelyabinsk-esque occurrence take place here, Boulder residents don't figure to lose much more than a window or two.

"Even if something fell out of the sky into Boulder, it's much more likely to land on the ground than on (a person)," Duncan said. "It won't be the size of a house or a football stadium or anything like that. Something that size probably only comes down once in a million years."